A rotor of this type is known from JP H 3-261354. This document discloses a steel cylinder, the surface of which is provided with a plurality of longitudinal grooves. The longitudinal grooves are relatively narrow at the surface of the cylinder and widen out beneath the surface to form substantially round cross sections. Copper rods are provided in the longitudinal grooves and are conductively connected to one another at their axial ends by copper short-circuit rings. According to the text of the document, the copper rods are connected to the cylinder by means of hot or cold isostatic pressing.
One drawback of the known rotor is that in reality it does not provide a connection between the rods and cylinder which is able to withstand the centripetal forces which occur at high rotational speeds. To the extent that there is any connection, this can only be ascribed to the positive lock between the rods and the longitudinal grooves, and not to the relevant materials bonding to one another.